From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH] tpm: don't destroy chip device prematurely Date: Sun, 2 Oct 2016 13:17:55 +0300 Message-ID: <20161002101755.GA25844@intel.com> References: <1475393971-12715-1-git-send-email-tomas.winkler@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1475393971-12715-1-git-send-email-tomas.winkler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Tomas Winkler Cc: tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net On Sun, Oct 02, 2016 at 10:39:31AM +0300, Tomas Winkler wrote: > In tpm_del_char_device device_del is called > prior to tpm2_shutdown where it is still used. > > Fortunately, so far chip->dev was used only for printouts > int tpm2_shutdown flow, hence system didn't crash. But with > the introduction of runtime power management it will result in > shutting down the parent device while it still in use. > > Fixes: 20e0152393b41 ("tpm: fix crash in tpm_tis deinitialization") > Signed-off-by: Tomas Winkler Tested-by: Jarkko Sakkinen Reviewed-by: Jarkko Sakkinen /Jarkko > --- > drivers/char/tpm/tpm-chip.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > index e5950131bd90..b1cb0aae8e66 100644 > --- a/drivers/char/tpm/tpm-chip.c > +++ b/drivers/char/tpm/tpm-chip.c > @@ -261,7 +261,6 @@ static int tpm_add_char_device(struct tpm_chip *chip) > static void tpm_del_char_device(struct tpm_chip *chip) > { > cdev_del(&chip->cdev); > - device_del(&chip->dev); > > /* Make the chip unavailable. */ > mutex_lock(&idr_lock); > @@ -274,6 +273,8 @@ static void tpm_del_char_device(struct tpm_chip *chip) > tpm2_shutdown(chip, TPM2_SU_CLEAR); > chip->ops = NULL; > up_write(&chip->ops_sem); > + > + device_del(&chip->dev); > } > > static int tpm1_chip_register(struct tpm_chip *chip) > -- > 2.7.4 > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot